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The lipase-catalysed transesterifications of 2-hydroxymethyl-1,4-benzodioxane in two different ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate, [bmim]PF6 and 1-butyl-3-methylimidazolium tetrafluoroborate, [bmim]BF4 and different organic solvents was studied. The hydrophobic and hydrophilic properties of ionic liquids and organic solvents do influence the lipase activity as illustrated from the results. The influence of the ionic liquid as an additive in an organic solvent on this reaction has been demonstrated. The enzymes in ionic liquids in combination can be recycled for several runs without substantial diminution in the lipase activity. [Copyright &y& Elsevier]

1-Butyl-3-methylimidazolium hexafluorophosphate ionic liquid was employed as a reaction medium for lipase-catalysed aliphatic polyester synthesis. Lipase PS-C exhibited excellent catalysis in polycondensation of diethyl octane-1,8-dicarboxylate and 1,4-butanediol at room temperature and at 60°C. A relatively high molecular weight polymer was obtained at 60°C. [Copyright &y& Elsevier]

Abstract: A hydroxyl group appended task specific ionic liquid was designed and synthesised. The ionic liquid was used as a vehicle for the substrate of our interest for lipase catalysed kinetic resolution. The ionic liquid anchored ibuprofen underwent Candida antarctica lipase catalysed hydrolysis yielding the S-enantiomer. The strategy facilitated easy post-resolution isolation of the enantiomers and also carries the prospect of recyclability. [Copyright &y& Elsevier]

Lipase-mediated regioselective biotransformations such as hydrolysis and alcoholysis of 3,4,6-tri-O-acetyl-d-glucal, 1 have been studied in organic solvent, tetrahydrofuran (THF) and two different ionic liquids, namely 1-butyl-3-methylimidazolium hexafluorophosphate, [bmim]PF6 and 1-butyl-3-methylimidazolium tetrafluoroborate, [bmim]BF4. The influence of different reaction media on the rates and regioselectivity of enzyme catalysis has been demonstrated. A marked regioselectivity towards the formation of 4,6-di-O-acetyl-d-glucal, 2 was observed in [bmim]PF6 with 84% product formation after 6 h with 98% selectivity in hydrolysis and 48% after 8 h with 98% selectivity in alcoholysis. [Copyright &y& Elsevier]